Nano Zero Valent Iron (nZVI) as an Amendment for Phytostabilization of Highly Multi-PTE Contaminated Soil.
TL;DR: In this article, the role of the enhanced nano zero valent iron (nZVI) strategy in the phytostabilization of soil contaminated with potentially toxic elements (PTEs).
Abstract: In recent years, a lot of attention has been given to searching for new additives which will effectively facilitate the process of immobilizing contaminants in the soil. This work considers the role of the enhanced nano zero valent iron (nZVI) strategy in the phytostabilization of soil contaminated with potentially toxic elements (PTEs). The experiment was carried out on soil that was highly contaminated with PTEs derived from areas in which metal waste had been stored for many years. The plants used comprised a mixture of grasses—Lolium perenne L. and Festuca rubra L. To determine the effect of the nZVI on the content of PTEs in soil and plants, the samples were analyzed using flame atomic absorption spectrometry (FAAS). The addition of nZVI significantly increased average plant biomass (38%), the contents of Cu (above 2-fold), Ni (44%), Cd (29%), Pb (68%), Zn (44%), and Cr (above 2-fold) in the roots as well as the soil pH. The addition of nZVI, on the other hand, was most effective in reducing the Zn content of soil when compared to the control series. Based on the investigations conducted, the application of nZVI to soil highly contaminated with PTEs is potentially beneficial for the restoration of polluted lands.
Citations
More filters
TL;DR: In this paper , the actual catalytic activity of Ni4/[email protected]3O4 under common ions and humic acid (HA) was investigated, and the results showed that Na+ and K+ had no effect on CT removal, Cl−, SO42− and low concentration of Mg2+ was beneficial to CT removal.
Abstract: Nanometer zero-valent iron (nZVI), Fe2+ and H2 were potential electron donors for CT removal by nZVI. However, the action of these electron donors in CT reduction was often ambiguous. In this study, the actual catalytic activity of Ni4/[email protected]3O4 under common ions and humic acid (HA) was investigated. The results showed that Na+ and K+ had no effect on CT removal, Cl‐, SO42‐ and low concentration of Mg2+ was beneficial to CT removal, while NO3‐, HCO3‐, Ca2+ and HA exhibited the negative effects. According to the analysis results of gas chromatography (GC) and ion chromatography (IC), a possible dechlorination pathway of CT was proposed. Furthermore, the action mechanism of nZVI, Ni0 and magnetite (Fe3O4) on CT removal were explored. Among the three possible nZVI reducing mechanism, the use of H2 by Ni0 for the hydrodechlorination was dominant, while the direct reduction of nZVI was secondary. Fe2+, the product of nZVI corrosion, contributed little to CT degradation and required longer reaction time. Ni0 could not only utilize H2 but also form galvanic cells with nZVI to accelerate CT dechlorination. In addition, the support Fe3O4 significantly improved the dispersion of Ni/Fe nanoparticles and its corrosion product Fe2+ also promoted the CT removal. These findings were significant for comprehending the mechanisms of bimetallic nanocomposites in reducing CT, and might guide to the development of nZVI based technology for repairing polluted water or soil with organochlorine pollutants.
5 citations
TL;DR: In this article, the authors applied a technique of aided phytostabilization for the immobilization of metal (-oid)s in soil with the application of nanosized halloysite and biochar (nBH), along with Lolium perenne L. Its effectiveness was assessed in terms of changing temperature conditions (16 cycles of freeze and thaw cycles, (FTC)) on the content of As, Cu, Pb and Zn in the soil, roots, and above-ground parts of the tested plant, chemical fraction distributions of metal and their stability (
4 citations
TL;DR: In this paper , the authors applied a technique of aided phytostabilization for the immobilization of metal (-oid)s in soil with the application of nanosized halloysite and biochar (nBH), along with Lolium perenne L. Its effectiveness was assessed in terms of changing temperature conditions (16 cycles of freeze and thaw cycles, (FTC)) on the content of As, Cu, Pb and Zn in the soil, roots, and above-ground parts of the tested plant, chemical fraction distributions of metal and their stability (based on reduced partition index, Ir).
4 citations
TL;DR: In this paper , a comprehensive review of the application of nanoscale zero-valent iron (nZVI) has garnered great attention as an adsorbent due to its low cost, non-toxicity, high porosity, and BET-specific surface area.
Abstract: In the last decade, the application of nanoscale zero-valent iron (nZVI) has garnered great attention as an adsorbent due to its low cost, non-toxicity, high porosity, and BET-specific surface area. In particular, the immobilization of nZVI particles onto inorganic and organic substrates (nanocomposites) decreased its agglomeration, allowing them to be effective and achieve greater adsorption of pollutants than pristine nanoparticles (NPs). Although nZVI began to be used around 2004 to remove pollutants, there are no comprehensive review studies about phosphate removal from aquatic systems to date. For this reason, this study will show different types of nZVI, pristine nZVI, and its nanocomposites, that exist on the market, how factors such as pH solution, oxygen, temperature, doses of adsorbent, initial phosphate concentration, and interferents affect phosphate adsorption capacity, and mechanisms involved in phosphate removal. We determined that nanocomposites did not always have higher phosphate adsorption than pristine nZVI particles. Moreover, phosphate can be removed by nZVI-based nanoadsorbents through electrostatic attraction, ion exchange, chemisorption, reduction, complexation, hydrogen bonding, and precipitation mechanisms. Using the partition coefficient (PC) values, we found that sepiolite-nZVI is the most effective nanoadsorbent that exists to remove phosphate from aqueous systems. We suggest future studies need to quantify the PC values for nZVI-based nanoadsorbents as well as ought to investigate their phosphate removal efficiency under natural environmental conditions.
3 citations
TL;DR: A greenhouse study was conducted to evaluate the effect of nano zero-valent iron (nZVI) on promoting plant growth and micronutrients uptake, reducing Cr availability in soil and rhizosphere as well as the accumulation and translocation of Cr in lettuce plant as discussed by the authors .
References
More filters
TL;DR: The surface elemental distribution maps of the nZVI@HCl-BC after reaction with Cr(VI) showed that Fe, Cr and O elements were deposited on the surface of Hcl-BC evenly, indicating that the formed Cr(III)/Fe(III) could settle on thesurface of HCl- BC uniformly rather than coated only on the n ZVI surface.
452 citations
TL;DR: A comprehensive overview on the field applications of various soil remediation technologies performed over the last decade or so is provided, and key knowledge gaps and practical challenges are identified.
281 citations
TL;DR: It is reported for the first time that Fe3O4 NPs often induced more oxidative stress than Fe3 O4 bulk particles in the ryegrass and pumpkin roots and shoots as indicated by significantly increased superoxide dismutase and catalase enzyme activities, and lipid peroxidation.
Abstract: To date, knowledge gaps and associated uncertainties remain unaddressed on the effects of nanoparticles (NPs) on plants. This study was focused on revealing some of the physiological effects of mag...
267 citations
TL;DR: Using a ZVI-biochar mixture as a soil amendment could be a promising strategy for safely-utilizing Cd and As co-contaminated sites in the future.
238 citations
TL;DR: In this article, the role of the oxide shell in the organic contaminant degradation efficiency and the molecular oxygen activation performance of nano zero-valent iron (nZVI) is discussed.
Abstract: Nano zero-valent iron (nZVI) has attracted much more attention for its potential applications in the fields of environmental contaminant remediation and detoxification Generally, nZVI consists of a zero-valent iron (Fe0) core and an iron oxide shell structure As the underlying Fe0 core and the surface oxide shell determine the physical and chemical properties of nZVI, the nature of the oxide shell inevitably affects the organic/inorganic pollutant removal performance of nZVI, which has not been reviewed previously In this article, we first introduce the synthesis and the oxide shell formation mechanism of core–shell structured nZVI and then discuss various characterization techniques to reveal the structure and chemical composition of the oxide shell Subsequently, we clarify the roles of the oxide shell in the organic contaminant degradation efficiency and the molecular oxygen activation performance of nZVI and also highlight the effect of the oxide shell on heavy metal removal (including As) with nZVI In addition, we summarize some oxide shell modification strategies to enhance the capacity and longevity of nZVI Finally, we discuss the impacts of typical natural groundwater constituents (eg cations, anions, organic ligands, and dissolved oxygen) on the reactivity of nZVI and point out some unresolved issues related to the oxide shell dependent contaminant removal properties of nZVI
224 citations